Or you're just derailing the thread bringing up stuff that will never get implemented. I recommend you look towards Futaisekai, as this game isn't going to give you the sort of content you are looking for.
Back to the ongoing topic:
The "Guardians" are mostly capable of growing bigger than we see. With the handful of times devs sadly just do a cheap angling of the images or enlarging a character's art to go beyond the cutoff of the frame with nothing to really give a sense of scale in such situations to date. Its all been their standard sizes in relation to everything else. Its' implied they can all grow multiple times larger, which with the increasingly disproportionate sizes that much more firepower would be needed to take them down. None of them have grown to their supposed maximum sizes to date. But given they are all seemingly capable aside just being big.... This is exactly why Diula was created as a weapon in the first place.